Fe1-xCoxTe0.5Se0.5系統在Li置入後的晶體結構與超導特性

Crystal structure and superconductivity in Li-intercalated Fe1-xCoxTe0.5Se0.5

李昊哲(Hao-Che Lee)

指導教授 ： 李文新

國立中正大學/理學院/物理學系/碩士(2015年)

摘要

本論文主要是研究一系列Li0.1Fe1-xCoxTe0.5Se0.5的晶體結構以及用Co取代Fe對超導和磁性的變化。我們以0.01的比例間格，製作了5個樣品。經由X-ray粉末繞射圖得知樣品皆是tetragonal單相，其space group為 P4/nmm。磁性量測的結果顯示，只有x = 0.01與x = 0.02有超導反磁訊號，TC分別為7.5 K以及7 K。說明了此鐵基超導系統只要以少量(≧2%)之Co取代Fe，即可將此鐵基超導性質完全破壞。此結果亦說明了鐵在此系統中鐵離子之有序性與其超導性有很大之關係。

關鍵字

超導體

並列摘要

This thesis is to study the crystal structure as well as a series of Li0.1Fe1-xCoxTe0.5Se0.5 replace the superconducting and magnetic properties of Fe changes with Co. Our ratio of 0.01 between the grid, made five samples. That by X-ray powder diffraction pattern samples are all tetragonal single phase which space group is P4 / nmm. The results of magnetic measurements showed that only x = 0.01 and x = 0.02 superconducting diamagnetic signal, TC 7.5 K, respectively, and 7 K. It illustrates this iron-based superconducting systems as long as a small amount (≧ 2%) of the Co-substituted Fe, this iron-based superconducting properties can be completely destroyed. This results also indicate that the iron in this orderly system of its iron superconductivity of a great relationship.

並列關鍵字

superconductor

參考文獻

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